


Codename: Kitty

by DarkBalance



Series: The Adventures of Chat Noir & Kitty Noire [5]
Category: Miraculous Ladybug
Genre: AU, Adrien Agreste/Marinette Dupain-Cheng Fluff, Adrien and Marinette are siblings, Adrinette April, Adrinette April 2020, Adrinette friendship, Age Regression/De-Aging, Alternate Universe, Big brother Adrien Agreste, Crack?, Cuddling, Doting Adrien Agreste, Fluff, Gen, I'm not sorry, LITERALLY, Marinette Dupain-Cheng Needs a Hug, Tooth Rotting Fluff, how is sibling AU not a thing?, probably
Language: English
Status: Completed
Published: 2020-04-13
Updated: 2020-04-13
Packaged: 2021-03-07 23:15:48
Rating: Not Rated
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,420
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26655754
Author URL: https://archiveofourown.org/users/DarkBalance/pseuds/DarkBalance
Summary: Marinette is so certain her big brother is going to be kidnapped and replaced with a wax statue that she's having nightmares. Adrien suggests they use security questions just in case it actually happens.
Relationships: Adrien Agreste | Chat Noir & Marinette Dupain-Cheng | Ladybug
Series: The Adventures of Chat Noir & Kitty Noire [5]
Series URL: https://archiveofourown.org/series/1697335
Kudos: 27
Collections: Adrinette April 2020





	Codename: Kitty

**Author's Note:**

> Has anyone ever watched the Doctor Who episode "Blink!"? My 27-year-old sister is horribly afraid of statues now because of it. She may or may not have been the inspiration for this chapter.
> 
> This day five of Adrinette April: "statue."

Marinette Agreste was a tough child. It was almost unnatural how resilient the little girl was. Adrien has watched his baby sister fall down entire flights of stairs and jump up with only a few elbow scuffs. She’s run into walls and bounced back with a smile. She nearly drowned in a swimming pool once but absolutely refused to come out of the water because how else was she going to learn how to swim?

(Adrien had a similar experience at the same age. It took three weeks, a bribe from his mother and a very stern conversation with his father to convince Adrien that it was worth trying again).

(At fifteen, Adrien is still not convinced it was a fair deal, and that’s without the Black Cat Miraculous magic.)

Marinette has been kidnapped by approximately four Akuma in the last six months and not a single time did she cry and beg for her parents (except for the once when she cried for her brother).

(But that was also because she saw him fall over the side of a building and thought he was dead, so it didn’t count).

No, it took a museum full of wax statues for Marinette to go screaming and crying for her parents to take her home.

=====

“Adrien?”

Adrien shivered when he felt the cold air from the bedroom flood the warm blankets surrounding him. The mattress behind him sank and, a short moment later, a small hand pat his body with what seemed like no rhyme or reason. Even a month after the incident, Marinette would still sometimes wake up in the middle of the night from a nightmare.

“Princess?”

“You’re okay?” Mariette’s voice, normally so loud and lively, was small like she was fighting tears. “You have all your arms? And legs? And your head?”

“Of course, I do,” said Adrien. He yawned and pulled his sister into his stomach, wrapping his legs around the little bit of her that he could and resting his head upon hers “See? How else can I wrap you all up?” He used the tips of his fingers to just slightly squeeze her sides, eliciting a reluctant giggle from her. “Why? What’s wrong?”. Normally, Marinette would simply slide into his bed and tuck herself under an arm or sprawl across his stomach. This was the first time she woke him up to talk.

“I dreamed we were playing in the park. And then you turned into wax and you melted and your arms and legs was falling all over the place.” Adrien squeezed Marinette a little tighter. Their mother normally stroked her face, and if their father felt particularly affectionate he would pat them on the head. Sometimes those helped to soothe her, but Adrien happened to know that nothing would work better than a warm, secure hug.

“Ah… those wax statues were kind of creepy, huh?”

“Mm-hmm.”

“...Do you want to hear a secret?”

“What?” said Marinette

“They creep me out too.”

“Really?”

“Really really,” said Adrien. “They look so real! I bet I could stand next to the one of me at the museum and no one could tell us apart.”

“I don’t like you being there. What if someone took you away from me and replaced it with a wax statue?” As intelligent as Marinette was, she was only six, and she got fixated on some really strange ideas. The wax museum’s attraction was how realistic the statues all looked; naturally, that would be what Marinette disliked the most about them.

“Wow, that is scary.”

“I know! We should tell Papa to call the museum and make them take you out of it.”

“Hmm.. we could, yeah.”

“Yeah?”

“But then there’ll be a wax statue here and I don’t think you’ll like that very much either.”

“I don’t want it anywhere. They should throw it away. Or melt it. Turn it into stupid Ladybug.”

“Hey, Ladybug is not stupid.”

“Says you. Chat Noir is a better hero.” Adrien smiled. Of course, Marinette would be a Chat Noir fan, she only adored her big brother more than anyone in the world. Why would a mask matter?

“I can’t argue with you there, Princess. Chat Noir is rather _claw_ some.” Hearing the pun get a proper laugh from Marinette, Adrien loosened his hold on her just enough that he could be comfortable in his own bed again. “How about we make up a codeword? Or a secret question? Something only you and I know. That way, if I’m ever kidnapped and replaced with a wax statue, you’ll know right away, and can tell the police to rescue me.”

“And Chat Noir?”

“You can tell him and Ladybug too.”

Adrien could hear his sister’s scowl in the silence. For some reason, she really did not like Ladybug, but her affection for Chat Noir was preventing her from arguing.

“What kind of codeword?” Marinette finally asked.

“It can be anything,” said Adrien. “It can be a special greeting that I say every time I see you. It can be a secret nickname. It can be a question that no one else can answer but us.”

“You have to call me Princess all the time,” Marinette decided after another quiet minute. She wiggled in his arms again, this time turning so that they were face-to-face. “Maman and Papa always call me Marinette. I like when you call me Princess.”

“Okay then. From now on, you’ll always be my Princess,” he punctuated the declaration with another squeeze to her sides. This time, Marinette squealed and squirmed in his arms. Adrien smiled to himself. “What about for me? What if someone replaces you with a wax statue?”

“Hmm… How about I call you… Kitty?”

“Kitty?”

“Uh-huh!”

“Why Kitty of all things?”

“Because you’re Chat Noir, silly!”

“Huh?”

“I saw you jump out the window!”

“You did?”

“Yep! You glowed green and then you were Chat Noir and you jumped out the window and saved Paris.”

Adrien’s heart raced. When was that!? How long has Marinette known literally the only and most important secret he’s ever had? Did she tell their parents? Her friends? Adrien had thought that she was being held hostage because their father had a strange penchant for causing Akuma attacks, but maybe it was because Marinette had told the wrong person she was Chat Noir’s baby sister?

“Did… did you tell anyone?”

“Nope! It’s our secret.” Marinette’s voice dropped into a dramatic whisper just before she burst into a fit of giggles. Her declaration made Adrien feel better, and his heart slowed to a less erratic pace, but he still didn’t feel as secure as he had just a moment before. God, Ladybug was going to kill him if she ever found out. Hell, Plagg was going to kill him. Probably. Maybe.

(When Adrien stops panicking and actually thinks about it, he’ll realize that Plagg was a little too lazy to put in the effort.)

(And then he’ll remember Cataclysm.)

“So we’ll be Princess and Kitty.”

“Yes!”

“So if I don’t answer to Kitty --”

“And you don’t call me Princess?”

“Yes, if I don’t call you Princess and I don’t respond to Kitty --”

“You’re a wax monster!”

“Yes, that, or just an imposter, a bad person pretending to be me. So you should go to the police or Ladybug or Mother and Father and tell them to go find me.”

“Okay.”

“Do you feel better now?”

“I feel sleepy now,” said Marinette. Adrien chuckled. He moved, starting to rearrange their position again. In the end, Marinette lay across his chest, arms clutching his middle as if he were a life-sized teddy bear. She was asleep in seconds, while Adrien held her and thought. Marinette was a clever girl, he’s known that since before she could talk. Marinette was always surprising him, for better or for worse, and this time was no different. Adrien was just grateful that it was Marinette who discovered his secret and not one of the housekeepers or their parents. However, he still wasn’t so sure it was a good thing.

There’s not much I can do about it now, I guess, thought Adrien. He mentally shrugged, deciding to talk to Plagg first thing in the morning and put up with the tiny god’s temper then.

(It’s now when he remembers that Plagg is too lazy to kill him.)

(It’s when he’s nearly asleep when he remembers that Ladybug is not.)

(And then he remembers Cataclysm exists.)

(Adrien may have a few nightmares himself.)


End file.
